Answer:
A) 0.0107
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean and standard deviation
, the z-score of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Mean of 440 seconds and a standard deviation of 40 seconds.
This means that
Find the probability that a randomly selected boy in secondary school can run the mile in less than 348 seconds.
This is the p-value of Z when X = 348. So
has a p-value of 0.0107, and thus, the correct answer is given by option A.